Turtle Modular Tunnel

function clearCol()
    turtle.dig()
    turtle.forward()
    turtle.digUp()
    turtle.digDown()
end

function selectItem(query)
    for slot = 1, 16, 1 do
        turtle.select(slot)
        if turtle.getItemDetail() then
            if turtle.getItemDetail().name == query then
                return true
            end

            if slot == 16 then
                return false
            end
        end
    end
end

function placeTorch()
    currentSlot = turtle.getSelectedSlot()
    if selectItem("minecraft:torch") then
        turtle.placeDown()
    end
    turtle.select(currentSlot)
end

TORCH_FREQ = 8
DISTANCE = tonumber(arg[1])

for i = 0, DISTANCE, 1 do
    clearCol()

    if i % TORCH_FREQ == 0 then
        placeTorch()
    end

    if turtle.getFuelLevel() < (DISTANCE - i) then
        shell.run("refuel")
    end

end